AUTHOR=Ding Xiangyu , Zhang Haimiao , Li Ming , Yin Ziyi , Chu Zhaohui , Zhao Xiangyu , Li Yang , Ding Xinhua 

TITLE=AtMYB12-Expressing Transgenic Tobacco Increases Resistance to Several Phytopathogens and Aphids

JOURNAL=Frontiers in Agronomy

VOLUME=3

YEAR=2021

URL=https://www.frontiersin.org/journals/agronomy/articles/10.3389/fagro.2021.694333

DOI=10.3389/fagro.2021.694333

ISSN=2673-3218

ABSTRACT=<p>Phytopathogens and pests are two major factors that limit the growth of plants. The expression of a flavonoid regulator gene, <italic>AtMYB12</italic>(<italic>AT2G47460</italic>), has been reported to increase the endogenous flavonoid content of tobacco and tomato. Previous research has only focused on the regulation mechanism of <italic>v-myb avian myeloblastosis viral oncogene homolog</italic> (<italic>MYB</italic>) transcription factors under single stress conditions. Here, research showed that <italic>AtMYB12</italic> was involved in regulating the resistance of tobacco to multiple biological stresses such as phytopathogens and aphid. We reported that transgenic tobacco carrying <italic>AtMYB12</italic> was more resistant to <italic>Ralstonia solanacearum</italic> when the up-regulated expression of several defense-related markers, such as <italic>NbPR1a, NbNOA1</italic>, and <italic>NbrbohB</italic>, was activated, suggesting that the priming defense of a plant may contribute to bacterial disease resistance. The improvement of the resistance of <italic>AtMYB12-expressing</italic> transgenic tobacco is achieved by promoting the production of ROS, H<sub>2</sub>O<sub>2</sub>, and NO. <italic>AtMYB12-expressing</italic> transgenic tobacco also has resistance to fungal pathogens, such as <italic>Colletotrichum nicotianae</italic> Averna and <italic>Alternaria alternate</italic>. The enrichment of flavonols components, such as rutin, which directly inhibit the growth of <italic>C. nicotiana</italic>e and <italic>A. alternate</italic>, may also contribute to the defense mediated by <italic>AtMYB12</italic> over-expression. At the same time, the results also confirm that <italic>AtMYB12-expressing</italic> transgenic tobacco enhanced plant resistance to aphid-infested (<italic>Aphidoidea</italic>) pests. These results suggest that the <italic>AtMYB12</italic> gene is a good candidate for pest and disease control, with limited resistance costs and enrichment in flavonols, and that <italic>AtMYB12</italic> has a potential in the breeding of disease-resistant tobacco crops.</p>